John Callen as Oin, Dean O'Gorman as Fili, Aidan Turner as Kili, William Kircher as Bifur, James Nesbitt as Bofur, Adam Brown as Ori, Jed Brophy as Nori, Graham McTavish as Dwalin, Ken Stott as Balin and Stephen Hunter as Bombur in "The Hobbit: The Battle of the Five Armies." (Todd Eyre / Warner Bros.)

Graham McTavish as Dwalin, Jed Brophy as Nori, Ken Stott as Balin, John Callen as Oin, Dean O'Gorman as Fili, William Kircher as Bifur, Aidan Turner as Kili, Adam Brown as Ori, Peter Hambleton as Gloin, Mark Hadlow as Dori, Martin Freeman as Bilbo and Stephen Hunter as Bombur in "The Hobbit: The Battle of the Five Armies." (Warner Bros.)

Even for the stars of “The Hobbit: The Battle of the Five Armies” the film’s impressive visual scale can come as something of a surprise.

At a special Hero Complex fan screening of the film on Dec. 11 at New York’s AMC 34th Street 14 & IMAX, actors Lee Pace, who plays the Elven king Thranduil, and Richard Armitage, who stars as the dwarf king Thorin Oakenshield, explained what it’s like to watch director Peter Jackson’s vision unspool on screen after having spent so much time on the New Zealand set.

“You see a lot of stuff that you never knew was there when you were shooting it,” Pace said. “I remember talking to Pete about the army, ‘It’s going to be a big army, right?’ ‘Oh yeah, it’s going to be big.’… Then I watch the movie back and it’s 10 times bigger than I ever imagined.”

Watch a clip from the conversation below, but for those who haven’t yet seen the movie, be warned that the conversation does include some minor spoilers.

The final installment in Jackson’s epic “Hobbit” trilogy, “Five Armies” picks up where last year’s “The Desolation of Smaug” ends, with Thorin and company, accompanied by Martin Freeman’s good-natured hobbit Bilbo Baggins, having reclaimed the treasure of their lost homeland Erebor from the evil dragon Smaug (Benedict Cumberbatch).

A vengeful Smaug heads to Lake-town to decimate the nearby village of men, and the destruction the dragon causes leaves the townspeople insisting upon recompense from the dwarves who disturbed his resting place, setting into motion the conflict that will grow to include the armies of the title.

“It’s very much like a thriller. That’s the tone of it,” Jackson told Hero Complex. “I’m not letting that tone go for a second. It gives me a chance to feel like I’m making a different movie, not something that has the familiar elements that we’ve had in the past.”

To find out first about upcoming films that will be featured in the Hero Complex Screening Series, follow us on Twitter: @LATherocomplex.

And check back soon for more clips from the conversation with Pace and Armitage, or read our in-depth interview with Armitage here.